Diagnostic Performance of Insulin Resistance Indices for Identifying Metabolic Dysfunction-Associated Fatty Liver Disease.

ABSTRACT

Background/objectives: Insulin resistance (IR) plays an important role in metabolic dysfunction-associated fatty liver disease (MAFLD) pathogenesis. A modified triglyceride-glucose (TyG) index, including TyG-body mass index (TyG-BMI) and TyG-waist circumference (TyG-WC), has been introduced to represent IR. This study aimed to investigate the diagnostic abilities of IR indices in MAFLD, in which fatty liver was diagnosed using computed tomography (CT). Subjects/methods: We retrospectively analyzed the clinical data and images of 852 adults aged ≥19 years who underwent abdominal CT. MAFLD was diagnosed based on the appearance of fatty liver on CT alongside at least one of the following three criteria being overweight or obese, at least two metabolic risk abnormalities, and/or diabetes mellitus. IR indices were calculated by examining the following variables homeostasis model assessment-IR, TyG index, TyG-BMI, TyG-WC, and visceral adiposity index. The diagnostic accuracy was evaluated using the area under the receiver operating characteristic curve. Results: For all patients, the area under the curve (AUC) of the TyG index, TyG-BMI, and TyG-WC were 0.834, 0.938, and 0.942, respectively. In men, the AUC of the TyG index, TyG-BMI, and TyG-WC were 0.812, 0.928, and 0.934, respectively. In women, the AUC of the TyG index was 0.841, and TyG-BMI and TyG-WC were 0.940 and 0.953, respectively. The AUC values tended to increase in the following order TyG index < TyG-BMI < TyG-WC. Women showed a higher AUC than men in all items, and the TyG-WC of women showed the highest value with AUC 0.953 (95% confidence interval [CI] 0.892-1.000, P < 0.0001). The AUC of the TyG index was 0.858 (95% CI 0.828-0.888, P < 0.0001). Conclusions: In conclusion, TyG-WC is a powerful surrogate marker for identifying MAFLD in clinical settings.